Synthesis, Characterization, and Anti‐amoebic Screening of Core‐Modified 5,20‐Bis{2‐{[(alkyl)(alkyl′)amino]methyl}ferrocen‐1‐yl}‐10,15‐diphenyl‐21,23‐dithiaporphyrin (=1,1″‐(10,15‐Diphenyl‐21,23‐dithiaporphine‐5,20‐diyl)bis[2‐{[(alkyl)(alkyl′)amino]methyl}ferrocene]) Derivatives

The synthesis of the first bis‐ferrocenyl‐substituted core‐modified porphyrins, 5,20‐bis{2‐{[(alkyl)(alkyl′)amino]methyl}ferrocen‐1‐yl}‐10,15‐diphenyl‐21,23‐dithiaporphyrin derivatives 6a – 6j , via a multistep route is reported ( Schemes 1, 2 , and 4 ). The synthesis was carried out through acid‐catalyzed (BF 3 ⋅Et 2 O) condensation of 1,1″‐[thiophene‐2,5‐diylbis(hydroxymethyl)]bis[2‐{[(alkyl)(alkyl′)amino]methyl}ferrocenes] 4a – 4j with 2,2′‐[thiophene‐2,5‐diylbis(phenylmethylene)]bis[1 H ‐pyrrole] ( 5b ) in presence of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (=4,5‐dichloro‐3,6‐dioxocyclohexa‐1,4‐diene‐1,2‐dicarbonitrile; DDQ). Characterization of the compounds was done at each step by means of various spectroscopic techniques. The final compounds were screened for in vitro anti‐amoebic activity against the strain HM1 : IMSS of E. histolytica ( Table 2 ).